Projectile radio sonde



IPBIOE OR Aug. 4, 1953 Filed Nov. 22, 1949 H. E. TATEL ETAL PROJECTILE RADIO SONDE 2 Sheets-Sheet l LF Oscillators INVENTOR. HOWARD E. TATEL EDGAR W. TRAINER ATTORNEY Aug. 4, 1953 H. E. TATEL ET AL 2,647,991

PROJECTILE RADIO SONDE Filed NOV. 22, 1949 2 Sheets-Sheet 2 FIG. 3

IN V EN TOR. HOWARD E. TATE L E D GAR W. TRAINER ATTORNEY Patented Aug. 4, 1953 UNITED STATES PATENT OFFICE PROJECTILE RADIO SONDE Howard E. Tatel, Silver Spring, Md., and Edgar W. Trainer, Rochester, N. Y., assignors to the United States of America as represented by the Secretary of the Navy Application November 22, 1949, Serial No. 128,742

6 Claims. 1

The present invention relates to a radio sonde for use in a projectile.

More particularly, the invention relates to a compact telemetric transmitter which can be mounted in the body of an expendable, streamlined ram-jet or rocket projectile.

With the advent of guided missiles and the institution of considerable research as to their characteristics, a great need arose for a method and means of installing electronic contrOl and/ or telemetric equipment in the test missile for the purpose of establishing a radio control link to the missile and/or for relaying to the ground information of the forces acting on the missile while in flight. To meet this need, electronic sonde equipment which could be mounted within test rocket or ram-jet projectiles, and which would not impair the aerodynamic qualities of such projectiles, had to be devised.

One object of the present invention, therefore, is to provide a method and means for packaging electronic sonde equipment for use in streamlined rocket or ram-jet projectiles.

More specifically, an object of the invention is to provide a simple and compact radio sonde which can be easily mounted within the body of a streamlined projectile without impairing its aerodynamic qualities.

Another object of the invention is to provide a telemetric sonde which is capable of converting a mechanical indication of a force acting on an airborne projectile into a radiant energy signal, and which does not impair the aerodynamic qualities of a projectile in which it is mounted.

A further object of the invention is to provide a cheaply constructed telemetric sonde which is expendable and which can be mounted within a rocket or like projectile.

Other objects and many of the attendant advantages of this invention will be appreciated readily as the same becomes understood by reference to the following detailed description, when considered in connection with the accompanying drawings, wherein:

Fig. 1 is a circuit diagram of a two channel telemetric system showing the electrical relation of the mechanical pickups and the radio transmitter that constitutes the system.

Fig. 2 is a perspective view showing the physical construction of the transmitter unit of the telemetric system.

Fig. 3 is a perspective view showing the physical arrangement of the entire telemetric system shown in Fig. 1, constructed in accordance with the present invention.

. 5 Fig. 4 is an axial section of a ram-jet projectile showing, diagrammatically, the telemetric system of Fig. 3 mounted therein.

The telemetric system illustrated schematically in Fig. 1 of the drawings comprises a radio frequency oscillator I0 having its tank coil I2 coupled to an antenna I3. Coupled to the oscillator I0 is a reactance tube modulator I41 which is controlled in its action by a pair of low frequency subcarrier oscillators I6 and I8. The tank circuit of subcarrier oscillator I6 includes a grid inductance 20 and a plate inductance 22 both of which are wound on a variable reluctance core 2i, and the tank circuit of subcarrier oscillator It includes a plate inductance 26 and grid inductance 28 wound on a common core 30. The two cores 24 and 30 in conjunction with their respective coils operate as telemetric pickups and as herein embodied are of the variable reluctance type, but may be of any other suitable construction, depending upon the nature of the information desired. The force to be measured varies the inductance of coils 20, 22 or 26 and 28, thereby varying the output frequency of the subcarrier oscillators I6, I8. By tuning the oscillators I6, I8 to different frequencies, theinformation supplied by one can be differentiated from the information supplied by the other and the output of the two oscillators can be superimposed on the output of radio frequency oscillator I0 and transmitted to a remote receiving station.

Referring now to Fig. 2, the preferred physical arrangement of radio frequency oscillator I0, modulator I4 and subcarrier oscillators I6 and I8 that constitute the transmitter assembly is shown. Radio frequency oscillator tube Ill is contained within its tank coil I2 to which antenna lead 49 is connected, and is mounted on a common base with reactance tube modulator I4. This assembly, alon with subcarrier oscillators I6 and I8, is secured to a curved chassis 36 having the proper curvature to fit the projectile in which the transmitter assembly is to be mounted. and the entire unit is covered over with a potting compound, such as wax, which serves to hold the components of the circuit in position despite the influence of high rates of acceleration and shock. As shown in Fig. 3, the transmitter assembly 38 contained within a potting compound is mounted on an annular chassis 40 along with a power supply battery 42 having an arcuate casing, a power supply switch 44 and telemetric pickup units 46 5 used.

The preferred manner of mounting the sonde prdfe'ctile'fifljdiiclijjb v "While'tliis s'onde has been disclosed for use in of Fig. 3 in the ogival nose section of a projectile is illustrated in Fig. 4 of the drawings. Fig. 4 shows an axial sectional view of a ram-jet projectile 60 having a central, open passageway 50 formed therein. Concentric with passageway 50 is a hollow, annular chamber 52, in which the sonde 54 is mounted. Also mounted in chamber 52 is a rod antenna 55 which is supported by sonde 54 and connected to the transmitter assembly thereof through antenna lead 49. The assembly thus mounted can then be used to transmit information of the forces acting gn a. ram-jet projectile, its adaptability to use in a rocket or other streamlined, cylindrical projectile is thought to be obvious. In addition, the number of telemetric channels used may be increased from two to three, or four or more, depending upon the information desired.

Other modifications and variations, such as the construction of a command guidance receiver, etc., in accordance with the above teachings, are thought to be obvious. It is therefore to be understood that within the scope of the appended claims, the invention may be practised otherwise than as specifically described.

What is claimed is:

1. In combination, a cylindrical, streamlined pro ctile having an ogival nose, a hollow, annularc iiamfier formed in said cylindrical projectile and concentric with the longitudinal axis thereof an antenna mounted in said chamber, and a plurality omefiiteomponents arranged in an electronic circuit and mounted on an annular frame. said electronic circuit being mounted in said chamber and connected to said antenna.

2. In combination, a cylindrical, streamlined projectile having an ogival nose, a hollow, annular chamber formed in said cylindrical projectile and concentric with the longitudinal axis thereof, an agitenna mounted in said chamber, a radio frefil g lcn transmitter assembly having a radio frequency oscillator, a modulator and a plurality f ibsertlegsisualn sihators modulati the dfitput g f saidradiairequency oscillator, a pluralityof telemetric pickups for varying the output irequency of s pbarea,a it rs. a power supply battery for energizing said transmitter assembly and an annular frame, said transmitter assembly, mechanical pickups and power supply battery being mounted upon said annular frame in said annular chamber and said transmitter assembly being coupled to said antenna.

3. In a projectile having a substantially axially located bore extending therethrough, and having a nose surroundin the forward end portion of said bore, an annular cavity around said forward portion of said bore, a substantially annular source of electromagnetic radiation including an antenna associated therewith in said cavity around said bore and rigidly embedded in the portion of the projectile near said nose.

4. In an aerial missile of the ram-jet type having a substantially axially located bore extending therethrough, and having a nose surrounding the forward portion of said bore, an annular cavity in said forward portion, a source of electromagnetic radiation disposed symmetrically in said cavity around said bore near said nose, and potting compound embedding said source and completely filling the remaining space in said cavity and rigidly supporting said source.

5. In a projectile having a substantially axially located bore extending therethrough, and having a streamlined nose portion surrounding the forward end portion of said bore, an annular chamber at said forward end and substantially concentrically encircling the bore, and an antenna and electronic components operatively associated with said antenna and housed within saidchamber.

6. In an aerial missile of the ram-jet type having a substantially axially located bore extending therethrough, and having a streamlined nose portion surrounding the forward end portion of said bore, an annular chamber at said forward end and substantially concentrically encircling the bore, a chassis within said chamber and curved to fit therein, an antenna and electronic components operatively associated with each other and with the antenna, carriedby said chassis and housed Within said chamber, and potting compound filling the remainder of the space in said chamber to keep the chassis and components immovable therein.

HOWARD E. TATEL. EDGAR W. TRAINER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,070,112 Bowles Feb. 9, 1937 2,199,555 Andrews May 7, 1940 2,310,017 Canon et al Feb. 2, 1943 2,478,866 Freas Aug. 9, 1949 OTHER REFERENCES Electronic Preserves, Scientific American, December 1947, pages 258 to 260.

Potted Subassemblies for Subminiature Equipment, Electronics, September 1949, pages 104 to 105.

Balloon Transmitters, Wireless World, June 1940, page 287.

Telemetering Guided-Missile Performance, Proc. IRE, November 1948, pages 104-1414 (page 1413 relied upon) Survey of Proximity Fuze Development, American Journal of Physics, March-April 1947, pages to (page 99 relied upon). 

